The Effect of using natural gas fuel on the performance and emissions of the spark ignited petrol engine

THE EFFECT OF USING NATURAL GAS FUEL ON THE PERFORMANCE AND EMISSIONS OF THE SPARK IGNITED PETROL ENGINE (M. Sc. Thesis) Ahmet KESKİN DUMLUPESfAR UNIVERSITY INSTITUTE OF SCIENCE AND TECHNOLOGY SUMMARY In this study, the effect of using natural gas fuel on the performance and the emissions of the modified spark ignited petrol engine was investigated. Natural gas pressure regulator, gas mixer and gas tube were used for modification. To use the advantage of the high octane number of the natural gas mel to increase the thermic efficiency of the engine, its compression ratio has increased by grinding the cylinder head within the allowed limits. As results, the values of the efficiency with natural gas was less than with gasoline. Also, considerable amount of decrease on the harmful emission values, especially HC and CO values was recorded. Nevertheless, the decrease of the cost of the specific energy is shown that as a fuel, natural gas is rather economical than gasoline. Key words: Spark ignited petrol engine, natural gas, compressed natural gas, natural gas engine.